<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>Document</title>
  <script src="./vuev2.5.21.js"></script>
</head>
<body>
    <div id="app">
      <my-com></my-com>
    </div>
  <script>
    Vue.component('myCom',Vue.extend({
      template:'<h1>我是h1</h1>'
    }))
    new Vue({
      el:"#app",
      data:{},
      mathods:{}
    })
  </script>
</body>
</html>